urban design process.ppt

5. URBAN DESIGN PROCESS
5.0 INTRODUCTION
Urban design is preoccupied with physical form and
functional quality of the city.
In terms of approach, it can be viewed as pure technique
and/or city building process among various actors
The nature of objectives will depend on the context and
scale/level of concern
Thus, at one extreme an urban design plan may be
specific including construction and financing details (project
level); On the other extreme, urban design may be generic;
simply entail a set of guidelines or rules, used to formulate
a policy that affects the decisions of others

5.1 Urban Design as Technique
I. Formal /Linear Process
 This is a logical process, through spatial and formal
means, that entails the following main stages:
1. Problem identification
2. Goal and Objective-setting
3. Situational analysis
4. Synthesis
5. Evaluation
6. Implementation

Problem identification
 What is not right?
 What liabilities?
 Whose problem?...who is affected?
 Why is it a problem?
 When is it a problem?
 Where?
 What does it call for?
….In a stable environment, this may seem a straight
forward thing….but in a pluralist environment (diverse),
there may be contested issues, stakes, and vested
inteersts!

Goal and Objective-setting
 Goals are fairly loose statements of principle that establish a
direction, and would hardly provide measurable variables for
gauging success.
 Objectives are translations of goals into something that is
achievable; hence their statement is more programmatic and
measurable.
 Urban design goals and objectives can occur at any scale of urban
design (macro to micro). An urban design scheme devoid of clear
goals and objectives can easily be dismissed.
 In contemporary societies, change is the norm and the goals of
individuals and groups are frequently at odds, making it complicated
a task to undertake.

Locale/scale Goal (example) Objective (example)
Region To engender a feeling of the
countryside into the city
To develop parks along all the
waterways that connect developed
urban areas and open countryside
City To maintain the downtown
area as a strong
metropolitan centre
To create economic incentives for
downtown reinvestment
Neighbourhood To reduce conflicts between
residential and industrial
land uses
To create visual and acoustical
buffers using fencing and
landscaping between all residential
property that abuts industrial land
uses
Block To maintain the sense of
visual enclosure that
presently exists on the
street
To limit new development to
existing building heights and
setbacks in conformance with
existing street character

Situational analysis
 Through inventories and other data collection techniques.
 Considerations:
land use, population, transportation, natural systems, and
topography; the varied character of areas, structure of
neighbourhoods, business areas e.t.c
 Central to understanding the structure, organization, and
pattern of urban areas
 Includes:
Visual survey;
Identification of hard and soft areas;
Functional analysis

Visual survey
 Graphic examination of the key physical elements and
functional character of an area.
 A vocabulary of symbols exist: edge, path, node,
landmark, district (after Lynch) that enables an urban
designer to characterize, in graphic form, the key
elements of the urban fabric.
 Visual survey is an urban design tool used to
communicate the perceptions of the structure and
organization of a city.
 Imageability/legibility: A more legible city makes us feel
less anxious about finding our way about in the city

Identification of hard and soft areas
 “Hard” and “soft” is concerned with “buildable” and “non-buildable”
and does not necessarily coincide with “built” and “unbuilt” .
 Delineation of the urban fabric into hard and soft areas assists the
designer in identification of the parts of the city that can
accommodate growth and change, against those that are essentially
fixed because they may be occupied by say historic monuments or
cemeteries
 Thus, a hard area may be a public park near the city’s central
business district that, despite the shortage of land, cannot be
identified for new construction. On the other hand, a soft area may
include neighbourhood or commercial district with an increasing
number of vacant buildings or with condemned building stock that
gives an opportunity for redevelopment.

Functional analysis
 This examines the relationship of activities among the
various land uses and how they relate to circulation
systems.
 This relates closely with the work of land use planners,
the difference being that the urban designer carries out
such a study into three dimensions.
 For instance, increase in building heights will call for
widening of streets to accommodate both motorized and
pedestrian traffic.

Synthesis
 Data collected and the analysis of the problem
are translated into design proposals for action
 Design concepts that reflect an understanding of
the constraints of the problem and propose
optimum solutions, based on tradeoffs such as
between motor traffic and pedestrians
 Main activities include:
Evolution of concepts for development
Development of schematic design
Preliminary Designs

Evaluation
 Based on two main criteria:
- How well the solutions fit the problem
- How readily the proposals can be implemented.
Thus, evaluation may examine:
ability to meet objectives
ability to gain public acceptance
meeting financial and technical demands

Implementation
 Devising the actual strategies for financing and
construction.
 Implementation relies on two main tools:
- Land use controls: include the traditional/Euclidean
zoning ordinance, Planned Unit Development,
Incentive/Bonus zoning, and Transfer of Development
Rights
- Capital expenditures: these shape the pattern of land
use by altering land values through the provision of
access and utilities.
 In this age of participation, successful implementation
of urban design projects will rely on both capital
expenditures and eminent domain (popularity).

 A visual survey is an examination of the form,
appearance, and composition of a city…an evaluation of
its assets (to be protected) and liabilities (to be
corrected.
 As an analysis of a city, its objectives are twofold:
- To establish the relationship between spatial
components as well as assessment of their condition
- To determine where the area investigated needs
improvement /reshaping/remodelling
A visual survey can be made at different urban scales:
macro to micro

 A visual survey calls for a descriptive
vocabulary for identification and relation
of spatial elements in order to understand
the form, function, and consequent
appearance of given space.
 A good survey generates ideas for action:
areas of improvement, correction or total
replacement.

Components of a visual survey
1. Image of the city
2. Landform and Nature
3. Local Climate
4. Shape of urban form
5. Size and Density
6. Pattern, Grain, and Texture
7. Urban Spaces and Open Spaces
8. Routes of movement
9. Districts/Enclaves/Sectors
10. Activity structure
11. Orientation
12. Details
13. Pedestrian areas
14. Vistas and skylines
15. Non-physical Aspects
16. Problem Areas

Image of the city
(paths, districts, edges, landmarks, nodes)
- the mental picture people extract from the physical
reality of the city
- a picture of parts of the city in physical relationship to
each other
- Picture of the most salient features of a city’s form
- Skeletal elements of city form
The more imageable the city, the more legible it is!

Landform:
 Every city is built on land
 Includes topography and landscape character…form of terrain (flat,
rolling, hilly e.t.c)
 Prominent landscape features should be noted….cliffs, ranges,
mountain peaks, rivers, lakes, e.t.c
 Type and character of greenery, including its seasonal changes
Landform and Nature

Nature: Considerations,
 Character of surrounding landscape that
built form will respond to functionally and
aesthetically
 Degree to which built form will enhance
nature
 Natural areas to be left intact to
complement urban form

Shape of urban form
 Characteristics and
objectives of various
shapes; pros and
cons.

Size and Density
 Size: physical extent; no. of inhabitants
 Density: population density; unit (dwellings)
density; amount of building floor area in a given
section of the city (floor area index); automobile
density
 Relationship of size and density influences the
population distribution and urban massing

Local Climate
 Temperatures: implications of seasonal temperatures and
humidity…averages and extremes…comfort zones and
periods…amelioration of extremes and discomfort
 Light: implications of clear and cloudy days
 Precipitation: rain and snow
 Sun: angles of the sun (solar altitude) at different seasons
affects viewing conditions…long and short sunny days
 Winds: direction and intensity of seasonal winds; cold and hot
winds

Pattern, Grain and Texture
 Pattern: the underlying
geometry of city
form…mostly define by
block and street layouts
 Grain: degree of fineness
or courseness in an urban
area
 Texture: the degree of
mixture of fine and
course elements of urban
form (even vs uneven)

Urban Spaces and Open Spaces
 Voids within the city
 Urban spaces:
formal…usually
modelled by building
facades and the city’s
floor
 Open spaces: natural,
representing nature in
the city

Routes of movement
 Principal
determinants of
urban form:
Routes affect the
appearance of the
landscape through
which they pass as
well as the
architecture and form
of cities they serve.

Routes of movement (cont’d)
 Clarity of routes in form and direction is a design
concern
 Routes should have physical relationships and help
define areas they serve instead of just slashing through
them, causing blight and disintegration
 Routes should artfully traverse the landscape, revealing
its strong features.
 Approach routes present cities to us and enable us to
fond our destination…thus they both inform and conduct
us.
 Surface arteries are major routes through the city…high
volume traffic
 Local streets carry a mixture of people and vehicles;
through traffic not desirable.

Evaluation of streets
 How streets tie together into the expressway pattern
 Clarity of form
 Relationship to cityscape
 How they shape building sites
 How they pass through existing districts
 Vehicular versus pedestrian traffic…any conflicts?...or
complementary?
 Crossing levels…specific or not defined: stoplights, grade
separation
 Through versus local traffic
 Scale…how size of streets relates to size of the districts
they serve

Districts of a city
 These are:
areas/precincts/quarters/
sectors/enclaves of the
city
 Often have dominant,
distinctive, and pervasive
characteristic features
 The city is an
arrangement of these.

Districts (cont’d)
 Districts may be distinct, overlapping, uniform,
complex.
 Two data categories to assess:
- Physical form
- Visible activity
 We assess:
- Components, appearance, activity, threats,
emergence, relations
 Anatomy of a district: form, activity, features,
paths, centres, intrusions, change, improvement

Activity structure
 This captures certain
areas of the city with
characteristic
functions…living, leisure,
learning e.t.c
 Activity structure will be
affected by density,
topography,
transportation routes.

Orientation
 This is the logical articulation of the
arrangement of a city’s anatomy
expressed visually
 A city lacking orientation is confusing and
may cause confusion, anxiety and feeling
of getting lost
 Landmarks are the prime aids in
orientation

Details
 These include objects of
various types for
direct/indirect or
conscious/unconscious
use: signs, benches,
waste bims, street lamps,
e.t.c
 The quality of detail
should be informed by
the nature of audience
targeted.

Pedestrian Areas
 These address walking as a
prime mode of
transportation…communication
and inter-movement.
 These should be creatively
integrated with motorised
transportation.
 Traffic calming is a specific
concern in design of
pedestrian areas…low speeds,
minimal through traffic, one
way streets e.t.c
Adequacy of pavements: widths,
paving, condition of repair, protection
from elements of weather, furniture
and fittings
Intersections and crosspoints: impact
on flow rates, continuity, and
sequence

Vistas and Skylines
 Vistas are strong visual links
 May serve approach or departure purposes of urban areas…i.e views
into and out of a city.
 Some views are gazetted and legally protected as urban assets
 Vistas could be complemented by buildings (ref. use of axis in
renaissance; civic design of Nairobi)

Skylines
Skyline refers to the (3-
dimensional) compositional
and sequential character of
urban spaces and buildings
 It is a representation of a city’s
facts of life and embraces the
maximum amount of urban
form in a single visual output.
 Every building with a potential
to alter a city’s skyline should
be studied carefully (ref. CBD
skyline exercise, B.A I)

Non-physical Aspects
 These are non-architectural aspects of
urban character that are still a large part
of a city’s image and personality
 Historical aspects, public ceremonies and
events

Problem Areas
 These have to be mapped out during visual
survey….
 The problem map represents urban design
diagnosis of ills!
 It may include: points of conflict (in land use,
circulation e.t.c); areas with little or no sense of
orientation; non-descript or grey areas; ugliness;
communities lacking form and definition; areas
with confusing signs; areas of decay and crime;
confusing circulation; incomplete routes e.t.c

Recording Results of a Visual Survey
 Visual surveys are commonly recorded as
simple maps accompanied by sketches,
photographs, and descriptive notes.
 The sketches, photographs, and
descriptive notes can be attached to the
map into an aggregate drawing or report

Visual Survey Recording Checklist
 A set of maps might include the following:
1. Topography
2. Microclimate – sun , wind, storm directions e.t.c
3. Shape
4. Patterns, textures, and grains
5. Routes
6. Districts
7. Landmarks and nodes
8. Open Spaces
9. Vistas
10. Magnets, generators, and linkages

Visual Survey Recording Checklist (cont’d)
11. Special activity centres and overall activity structure
12. Hubs of intense visual experience
13. Strong and weak areas of orientation
14. Sign areas
15. Points of conflict
16. Historic or special districts
17. Community structure
18. Areas of preservation, moderate remodelling, and
complete overhaul
19. Places needing clarifying design elements
20. Sketch maps of prominent urban features and form

5.2 Urban Design as Process
 Entails City Building action among various
parties
 Negotiation – by political-economic means
 Sectoral issues of importance
 Institutional Design; Community Activism;
eminent domain and their role in design
 Linking ideas to action (Urban trialogues);
Visions-Strategic urban projects-Co-production
(collective participation of actors)
 Leverage for resources; political processes;
community mobilization and involvement

 Urban design charters: commit Government agencies
to achieve good urban design when managing public places or
creating the public buildings and infrastructure that contribute to
the qualities of our streets, squares, parks and waterfronts.
II. Non-Formal/Non-linear Design Approach

Implementation models
(urban design as process)

Functional Analysis (software):
Employment/Occupational structures;
Demographic structure;
Neighbourhood Lifestyles/perceptions;
Procurement/ownership/ use patterns
Technology &materials;
Amenity and services;
Symbolic & aesthetic order;
Socio-political order:
Policy, institutions, and, governance.
Character
(Socio-spatial)
Physical Analysis (hardware):
-Morphology
-Building typology & construction
systems
-Image and public realm
-Objects & Aesthetic detail
-Infrastructural installations
Nature, Intensity, Location, and impact of Modernity
Community perception of Modernity
Projected Areas of (traditional-modern) Conflict and
Congruence
Adaptability of traditional to modern functions

urban design process.ppt

More Related Content

What's hot (20)

Similar to urban design process.ppt (20)

Recently uploaded (20)

urban design process.ppt